We propose a hybrid interface preconditioner for the monolithic solution of surface-coupled problems. Powerful preconditioning techniques are crucial when it comes to solving large monolithic systems of linear equations efficiently, especially when arising from coupled multi-physics problems like in fluid–structure interaction. Existing physics-based block preconditioners have proven to be efficient, but their error assessment reveals an accumulation of the error at the coupling surface. We address this issue by combining them with an additional additive Schwarz preconditioner, whose subdomains span across the interface on purpose. By performing cheap but accurate subdomain solves that do not depend on the separation of physical fields, this error accumulation can be reduced effectively. Numerical experiments compare the performance of the hybrid preconditioner to existing approaches, demonstrate the increased efficiency, and study its parallel performance.

中文翻译：

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用于整体式流固耦合求解器的混合接口预处理器

我们为表面耦合问题的整体解决方案提出了一种混合接口预处理器。当要有效地求解线性方程组的大型整体系统时，强大的预处理技术至关重要，尤其是在流固耦合等多物理场耦合问题中。现有的基于物理的块预处理器已被证明是有效的，但是它们的误差评估显示了耦合表面误差的累积。我们通过将它们与附加的Schwarz前置调节器组合来解决此问题，该前置器的子域故意跨接口。通过执行不依赖于物理场分离的廉价但准确的子域求解，可以有效地减少这种错误累积。